The driven van der Pol equation

There are many versions for the ``van der Pol’’ equation. Among them, there is this one, involving the cubic term, which reads

and which was investigated in details in [1]. This is sstem is a semi-conservative system which means that there is a continuum of attractors, that is, many many different attractors co-exist in the state space [2]. When parameter values are , , and , and initial conditions are